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New Solution to 16G Boost Creep

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bbarnumboy

10+ Year Contributor
52
1
Feb 20, 2012
Everett, Washington
This is My solution to boost creep, which has worked absolutely flawlessly for me. Please read on to see my how to, which has cost a total of 65$ for the modifications and about 1.5 hours of my time to do.


So as a new DSM owner, I have been searching extensively for a solution to my boost creep. As most of you have the same issue, I have a full 3" exhaust system, with a 16g internally wastegated on a 1G setup.

I have seen the Mrpeepers solution. This solution is to modify the stock wastegate actuator to increase the actuator arm traveling distance. I also know all about the porting of the flapper hole and also the upgrading to the 34mm flap. I know about the porting of he o2 pipe and the turbo etc.....
So one thing that kind of upsets me when i read all these discussions about boost creep, is the guys that say "how about you just deal with it, and get the supporting mods to fuel the extra boost?" So i do not know about you guys, but when i set a turbo vehicle at 18 psi of boost, i should spool quickly and right up to 18 psi. For the guys seeing Boost creep, they are seeing the pressure go straight up to the regulated wastegate spring pressure. After that it will stay at the pressure, lets say 10psi for a few thousand rps, and all of a sudden in the higher rpm's it is jumping way up over 20psi.

The goal here is to get the full 18 psi smoothly and to have it all come in at the same time. It irritated the crap out of me, to have to wait until 4500 rpm to get my extra 8 psi of boost to come in because it was just sitting at 10 psi since 2500 rpm.

In doing my research, I have noticed that the modifications being done to increase the wastegate actuator travel, are causing side effects. These side effects were that the spring in these new or modified actuators, were not strong enough. This results in the flapper being blown open at an early boost level, causing a slow spool up. The other effect was, if you increase the spring rate, then you would possibly be increasing your boost to a higher level, as well as increasing the boost creep with it as well.

Here is what i did to fix the issue on my car. Take note that the lowest i was able to get my boost to hold steady, was around 15-17psi without creeping. Any lower than that, I was still experiencing Boost creep. Right now i have mine set at 18psi and holding steady to redline. This may not work for everyone, but it has worked for me.

I purchased a Turbonetics 30326 for $65. This is a Turbonetics Wastegate actuator, that has a dual port on it, as well as an adjustable rod. Here is the picture below.

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So i have seen this actuator being used in many different ways. I decided to use it the way i want to. The pictures and steps to getting this actuator to fit on your 16G will be at the end of this post.

This actuator has approximately an 1 inch of travel!!! way more than the stock actuator. After i installed the modified actuator, i ran it using only the top port, as you would run the stock actuator. This actuator has about a 7LB spring in it. Running the car like this, gave me the same results as the stock 10lb actuator did. The boost would build up to 6.5psi (Mind you slowly because the flapper was being blown open.) After it would get to 6.5PSI at around 3,000 rpm, it would stay at 6.5 psi until about 4,500 rpm. Once it reached 4,500 RPM it would shoot straight up past 20 psi very quickly. This was the same Boost creep that i was experiencing with the stock actuator.

I decided i would utilize the second port on the actuator ( This is why i purchased this actuator.) My idea for this second port was as follows.

If this actuator has a 7 lb spring in it, and i run boost to the top and bottom port, it would equal out pressure on both sides of the actuator, resulting in no movement, because both sides are pressurized at the same pressure. This would just keep the flapper shut and run boost as high as it could. That is not what i want.
I hooked up a Manual Boost Controller to the bottom port (closest port to the actuator rod) and this is where i had my success and why purchased this actuator.

If my target goal of Boost is 20 psi, then i want my actuator to open all the way at 20psi, therefore regulating my boost. But i only have a 7lb spring in the actuator right? Easy, i set my manual boost controller at 13psi or less for the bottom port. In doing this i have added 13 lbs of force to the already 7lbs of the spring. The result is, that it will take 20psi of force to overcome the spring pressure, and regulate my boost.

It is like changing out the actuator spring, but doing it with pressure, While keeping pressure on the flapper from blowing open. All of this at the dial of a manual or electronic boost controller.
My results was a solid 18 psi to redline. The turbo spools so fast, since the back pressure of the bottom port is holding the flapper shut. I am seeing 10-13 psi at 2800 rpm or so. Just after 3-3500 rpm i am seeing my full regulated 18 psi. My boost now come is at full force, without taking a break. This is because i have now set the actuator at 18psi using boost pressure.

Below is my Mechanical how to, guiding those who wish to use this actuator.

Tools needed

-Cutting wheel or hack saw
-Marker
-Welder
-.250 1/4 inch drill bit and drill


First off, here is a comparison picture of the stock actuator vs. the new Turbonetics 30326 dual port actuator, in travel distance. The stock unit pulled around 3/8th of an inch. the Turbonetics moved about 1 inch. I marked the rod with an orange marker to show the travel distance.

Stock 16g unit
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Turbonetics unit
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Comparing the 2 units You can see that the new unit is much shorter. I set the 2 units next to each other. If you can see the orange markings on the rod, this is where i made my cut. I set the adjustable part of the new unit in the middle of the thread range. This will give me equal ability to tighten or loosen the rod in either direction. Set the units next to each other, cut the tip of the new unit off, and make a mark on the old unit showing where to make your cut. The goal here is to make the new unit the same length as the stock unit. We are going to use the stock units pre-bent portion.
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next cut the rod off of the stock 16G unit where you made your mark and clean of the rust :)
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Next cut the tip off of the new Turbonetics piece, leaving you a threaded sleeve. This is what we will be welding to the piece removed from the stock unit.
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Here is a picture showing the parts i cut off of each unit.
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Next, weld the piece that we cut off of the stock 16g actuator, onto the threaded sleeve of the new actuator
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At this point you can thread it onto the new Turbonetics Unit to see how it looks! Remember to get that rod welded as straight as possible, so we don't have to redo it later if there was an interference. See how nice that looks?
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Next, cut the bracket off of the stock actuator. I recommend doing this in a vise, because the spring is in there under pressure and will want to shoot out, creating a safety hazard. So be careful.
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Here is the bracket after i cut it off
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There are 2 nuts on the new Turbonetics actuator. holding a big washer on. This is where we will be mounting our new bracket that we cut off from the stock 16G unit. I realized after i was done, that i did not have to weld the bracket to this washer. What i did was weld the bracket to the washer after i determined how i wanted the actuator positioned. You can put it how you want, to get the vacuum nipples where desired. After you weld the washer to the new bracket, you need to drill the holes through, using the washer holes as a guide. If you want to, you could just clamp the washer to the bracket, drill the holes and you are done. But i went ahead and welded it on cause i like to weld.
here is the picture of the washer welded to the bracket, and the holes drilled. The bracket now slides onto the 2 bolts on the new actuator. Just install the 2 nuts that are provided and voila, it is complete.
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Now here are a few pictures showing the completed actuator, that is ready to install. Notice how much smaller it is than the bulky stock unit. looks great!

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I had no interference what so ever. It was a perfect direct install. Keep in mind that the rod is fully adjustable to get it where it needs to be, and that the rod can spin to get it lined up properly. Here are some pictures of it installed. Enjoy

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I hope this will help someone as it has helped me. It has been a success and took about 1.5 hrs to do the fabrication and install. The actuator is simple to remove and install. just 2 bolts hold it to the turbo, and a cotter pin or clip holds the end of the rod to the turbo.


I am just a new DSMer who found a way to make his boost creep go away. This could not have been done without the help of all the archived threads, of past ideas. This would obviously have alot more success if you added some porting to the turbo etc.... but my boost goal is higher that 15psi so i had success. I doubt this will help anyone with Boost creep, if your target PSI is below 15.

Thanks and let me know if you have any questions or anything else.
 
here is the last picture of the install

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This is a pretty legit deal here, and im not tryin to knock it in anyway. But it seems like a lot more time, work and money than just porting the existing wastegate housing, which after reading a how to, i decided to do. I ported the hole a little bit, kept the stock flapper, and ported the housing quite a bit as well all together taking me around 2.5 hrs, including removal and install. I had my boost holding steady as can be at around 10 psi, building that high steady at around 2000 to 2500 rpms...now i have my avcr set to 1.2 bar and it builds very nicely to around 16-17 psi and holds to redline.
 
i do not have it hooked to my dsmlink so no. Like i said a port job would compliment this well. It was very easy to do. Mind u the 1.5 hrs it took was also me figuring out how to do it at the same time. I just dont wanna pull the turbo LOL

I really wish this could be moved out of the newbie forum, because it is useful infirmation.
 
I would love to have a dual-port WGA to help me HOLD MORE boost with my 16G.

Get some cams and turn the boost up, and you'll have an issue the opposite of boost creep :).

So does the dual port just loop threw the mbc, allowing it to by-pass and hold the prefered pressure?
 
Wow.....looks familiar.

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If you're using a dual-port actuator, verify that the bottom port actually seals. Many have reported air just blowing through them on certain brands when they've given any sort of pressure.


Of course if you're seeking more pressure, you can use a stiffer actuator like those outlined in this thread:

http://www.dsmtuners.com/forums/tur...oking-strong-internal-wastegate-actuator.html


Many who have used these actuators have reported a reduction in boost creep as well as a reduction in spike/drop over the factory MHI actuator.
 
did you enlarge the stock 16g wastegate port?

No. as far as i know the 16G is 100% stock with the stock manifold and o2 housing.

Wastegate Actuator Assy, 7.5psi, Dual Port

This is from the website. The spring pressure sounds a little low to me. And I am also a bit confused on the dual port? Either way, love the idea.

I stated above that i was getting around 7 psi on the actuator because of the spring. When i ran it using only the top port, it was stalling at 7 psi then started to creep. But before i utilized the bottom port i had terrible spool up as well, so i know this is working as i figured it would.

Would it be possible to add a port to the bottom part of the stock WG? Or is it not sealed like the duel port WG?

I blew air with my mouth into the bottom port with no leaks. it has a greased plastic washer that seals under the metal washer i welded the bracket to. I also plugged the bottom port with my finger and forced the actuator and it did not leak air. I have heard of people adding a second port on a stock one, and it will not work. It leaks.


My main idea with getting this actuator was travel distance to open the wastegate flapper more. I called a business that had one in stock and told him to pull on it and measure it. I knew at that point i needed to buy it. The travel is alot more than stock. Unfortunately it comes with a weak spring in it, but that is why i am using the bottom vacuum port. It is using the boost to hold extra pressure against the spring side.


So does the dual port just loop threw the mbc, allowing it to by-pass and hold the prefered pressure?

Not sure what you mean here. But this is my setup.

A vacuum line straight from the intake manifold is running to the top port to give true boost pressure. I made a T off of that line to a boost controller. The boost controller output line then runs to the bottom port. I can adjust the manual boost controller, and it adjusts how much pressure (resistance) i wish to add to the spring side. very simple. With a 7 lb spring, it will take 7 lbs of force to open the wastegate. Every lb of pressure we run to the bottom port, using the manual boost controller, it is adding that lb of pressure to the spring side of the actuator, simulating a stronger spring. so if my MBC is set at 13psi, add that to the already 7LB spring, it should take 20+psi of true boost going to the top port to start forcing the actuator open.


Little side note. I am experiencing a little jump in boost in the cold. I hear this is a normal problem when people do this anyways. Not sure why, must be some physics crap.
 
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I have seen the Mrpeepers solution. This solution is to modify the stock wastegate actuator to increase the actuator arm traveling distance.
The distance the flapper opens has nothing to do with the amount of airflow that can exit through the hole.

If you drill a 1/2" hole in a barrel of water, then put your finger over the hole...no water comes out. Pull your finger away and water pours out- doesn't matter if your finger is 1/4" away or two feet away from the hole.

Another downside to having the flapper open too far is boost that drops off as the RPMs climp. With a smaller turbo, if you want to maintain the same boost pressure as the RPMs climb, the flapper needs to slowly close or your boost level will tank.

Proof that having a flapper that opens more doesn't necessarily work comes in this blog...and this is with everything ported as well.

Mr Peepers said:
Been fighting it for a while on other peoples' setups and been fairly successful. But of course, it ends up I can't cure it on my own

14b with a 7cm^2 turbine housing, 3" turboback with no cat, only a 3" vibrant resonator. Dejon super sidemount, piping, etc etc.

Ported the turbine housing for creep(twice since I thought I may have problems holding boost if I went too far) and moved the pin on the flapper arm so it could open near 90*. Creeps above 15 psi towards 20 around 4.5-5k. Unhooked the WGA arm completely so the flapper could be open ALL the way and it STILL creeps to 20 psi by 4.5-5k in higher gears.

Don't know what to do at this point, it's a 14b for crying out loud. Guess I'll just have to run 20ish psi, luckily I haven't seen more than 1 count of knock; oddly.

Now I'm not saying that what you've done here doesn't work, more like it may not work for everyone. ;)
 
Not going to argue that because I mostly agree. Yes i believe this will not work for everyone, as it barely worked for me. It is not perfect but it is a solution for now. Before i had no regulation, it just kept creeping.

In the end i am going to go external wastegate off an exhaust manifold. I don't like how everyone constantly says its stupid, waste of time and money or worthless to go external on a 16G. But funny enough, everyone seems to get boost creep with modifications and a lot of them get it after porting the turbine, wastegate hole, and the o2 housing or even the 34mm Flapper mod. Years and years of threads with hardly any results to this problem, and people will still say it is a waste to go external. I will simply hook up an external and i will probably never experience boost creep ever again. I will get a solid constant and reliable boost curve and pressure. Does not sound like a waste to me :)

On the other hand i was passionate about trying to fix it using the internal wastegate. I accomplished that, at least for my setup for now.

JusMX141 I just realized you were the one i contacted about the Holset actuator the other day. I wanted to go that route but i feared the spring was going to be too strong to hit my 20 psi goal.

I got the idea of a dual port from Mrpeepers thread i believe. Someone put up a picture of the Turbonetics dualport actuator and i went exploring the web to find out more about this actuator and how it works.

It is funny how the turbonetics looks exactly like Holset one you used. except mine has 2 ports.
 
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Decided to fix the problem for good. I put on an external wastegate setup. I also removed the flapper from the turbo and welded the flapper arm hole. I then ported the wastegate hole for even more flow. I have a 14psi spring in it right now and it holds 14psi solid. I see a spike to 15 in 5th gear pulls. but i am completely satisfied. Here are some pictures and a video of a 5th gear pull. Normally I would spike upwards of 25-30 psi...(that was before the actuator mod i did first)

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So since i removed the above Actuator by Turbonetics, i have it sitting here. Does anybody wanna try to see if it will help their setup?
 
i know i am reviving a post from nearly 10 years ago, but i want to highlight one thing so no one makes the stupid mistake i did.
the washer on the bottom of the turbonetics 30326 dual port wastegate holds in a plastic bushing in place
the plastic bushing pushes on an internal seal and seals the bottom port of the wastegate and around the shaft.
i did not know this and assembled my 16G wastegate bracket in between the bottom of the wastegate can and the washer [effectively spacing the washer away from the plastic bushing; therefore, the plastic bushing could not press on the seal to make it ..... seal].
this created a huge boost leak on the bottom of the wastegate and i didn't understand that i had assembled the thing incorrectly causing the boost leak [insert two weeks of confusion, and turbonetics was not answering their phones or returning calls].
i thought the washer was just a backing plate to be used to sandwich any turbo-specific bracket shape to the bottom of the wastegate.
what is shown in the images above and defined in post #13 ["it has a greased plastic washer that seals under the metal washer i welded the bracket to"] is correct, and i missed this detail.

after fixing the bottom port leak, i am still fighting how to make this work correctly with a turbosmart dual setting boost controller.
i get either all the boost [30+psi, too much air to the bottom wastegate port] or wastegate spring boost [~10psi for me, not enough air to the bottom wastegate port]; i have not yet found the right amount of air to flow to be within the adjusting range of the boost controller.
today i sourced some welding tips to use as inline flow restrictors [similar to the OEM setup with a 0.025" restrictor, see the bottom of this page : https://www.ecmtuning.com/wiki/bcsinstall ]
the tips i got for testing are :
> 0.023" [0.6mm]
> [the welding supply shop did not have the 0.030" [0.75mm] tip in stock, but that is also an option]
> 0.035" [0.9mm]
> 0.045" [1.2mm]
> and i drilled out a piece of brass rod to 1/16" [0.0625" or 1.6mm]

if none of this works, i will use an electronic boost control method, but for now i am experimenting and trying to keep the boost control based on mechanical means [personal preference].

just FYI that this could be an issue for you as well.
also FYI that i started this journey when i was blowing the OEM 16G wastegate open at around 22psi and i am trying to run around 25psi
anyway, i hope this helps someone.
 
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